I'm trying to make a simple stencil that can be placed on a plastic, plexiglass, or PVC-type surface, but the stencil I have is too small and detailed to be "cut out" the normal way. Any ideas?

make a mold of the stencil and use a liquid material instead

I don't understand. This stencil is printed out on paper, not 3-D.

What are you planning to do once you have the stencil? IOW how do you plan on transferring the stencilled design to the surface you need it on?

I don't understand. Just use an x-acto knife then.

Just use an x-acto knife then.

If the stencil is too detailed to be cut out with an X-ACTO, then Appolinaria's first suggestion is best. You'd basically be making a stamp you could coat with ink for your transfer.

Sounds good, but how do I take a printed-out image and transfer it onto a rubber stamp without an X-Acto?

You said the stencil was too small and detailed to be cut the normal way, so I just assumed you didn't have an X-ACTO knife. The only way I know how to make a stamp is with a very sharp knife, sort of like, well, an X-ACTO.

 

You take your printed stencil and go over it with a very soft pencil (#1) ON THE BACK SIDE (a light box would make this easier) to leave a graphite residue in a reverse image. Then you get a hard, flat, pink eraser and press the stencil graphite side down onto the eraser. This should transfer the image to the eraser. Then you use your X-ACTO knife to carefully cut away the excess eraser, and the parts on the interior of the stencil so that what you want to be printed is raised and flat. You can then use an ink stamp pad in whatever color you want.

The reversed image transfers when pressing? I guess I'll try it.